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REPORT OF THE SPECIAL COMMITTEE ON 
PREVENTION OF SMOKE. 


Your committee, charged with the duty of investigating the coal 
smoke problem, and making such recommendations as may tend to 
abate the evil which prevails in our city to so serious an extent, offer 
the following report as the result of a careful consideration of evidence 
accumulated not merely during the past year of this committee’s exist¬ 
ence but through many years, as well, of active interest in the various 
questions relating to the economical use of fuels. 

The subject will be discussed under the following general heads: 

I. Introduction. Importance of the Subject to all Classes of the 
Community. Misapprehension existing as to the Nature of the 
Problem. 

it The Principles and Reactions upon which Combustion de¬ 
pends. Conditions favorable for Producing Smoke and those required 
to Prevent. 

III. The Fuels used in St. Louis and their Relation to the Smoke 
Problem. 

IV. The Various Classes of Fuel Users and their Relation to the 
Smoke Problem. 

V. Conditions of Fuel Consumption under Boilers in St. Louis. 

VI. Requirements Necessary for a Satisfactory Smoke Preventing 
Device. 

VII. Classification of the Important Types of Smoke Preventing 
Devices and the Principles upon which they Depend. 

VIII. Experience in Other Cities relating to the Abatement of 
the Smoke Nuisance. 

IX. Conclusions and Recommendations. 



2 


Prevention of Smoke. 


Introduction. 

It may be said that St. Louis has suffered more than any other 
important city of the country from a combination of three conditions 
most unfavorable to the improvement and metropolitan development 
of any community, ist. unpaved or badly paved streets, 2 nd. water, 
if not unwholesome, at least unattractive and often repulsive in appear¬ 
ance, and 3 rd, an atmosphere polluted with coal smoke. Happily for 
this community the most serious of these handicaps has been removed 
and St. Louis may now claim to be one of the well paved cities of the 
country. The benefits of this improvement are so remarkable and 
so widely recognized that few among us will deny the beginning of a 
new era of developement and prosperity with the establishment of good 
pavements. The work of installing the main low service pumping 
plant at Chain of Rocks, far above the sources of pollution from city 
and suburban drainage is already well advanced, This change and 
the many improvements connected with it (some the results of investi¬ 
gations now in progress with a view to removing the mechanical sedi¬ 
ment and improving the quality of the water) will ere long give to the 
people of St. Louis a better service, and a water not only purer and 
more wholesome but unobjectionable in appearance. There will re¬ 
main then the purification of the atmosphere by the proper abatement 
of the smoke nuisance. With this secured not only may St. Louis 
boast of conditions upon which especially depend outward attraction 
and the comforts of living, but the community with the intelligence 
and energy to accomplish reforms such as these will be sought after 
as one possessed of the best elements of prosperity and progressive 
development. 

Of the three great problems referred to relating to the material 
improvement of the city that which seems to interest the greater num¬ 
ber of people and call for the more general comment and criticism is 
the smoke problem and yet it is, apparently, the one least understood. 
In its relation to this problem the community may be divided into three 
general classes, viz., the manufacturers and other large consumers of 
bituminous coal; the inventors and promoters of smoke preventing 
devices, and the general public. The manufacturers and other large 
coal users are mainly responsible for the production of the smoke. 
They may or may not have had experience with smoke preventing 
devices. If they have, they are as a rule disappointed because of the 
failure to secure'benefits recklessly promised. General indifference 

LC Control Number 



tmp96 030857 


Prevention of Smoke. 


3 


results, or an established belief that there is no satisfactory solution to 
the problem. The inventors and promoters of these devices stand 
ready with their universal solvents unable to understand why their 
efforts for the public good are so little appreciated. Their patent ap 
pliances are unsuccessful in some cases because of being founded upon 
an entire misconception of the underlying principles and reactions in¬ 
volved in the combustion of bituminous coal, or, in others, from a want 
of appreciation on the part of the inventors and users alike, of the corn 
ditions which fix the limitations of successful application. And lastly 
the general public, too ready to assume that a smoking chimney repre¬ 
sents wasteful combustion of fuel, inveighs on the one hand against 
the recklessness and want of enterprise in the manufacturers who con¬ 
tinue to pollute the air and on the other against inventors and even 
engineers and men of science for their indifference or want of skill 
while a problem which promises such rich rewards remains unsolved. 

It would seem, then, that as in the case of so many other questions 
of public concern, the whole community must be educated to a more 
intelligent understanding of the problem before a satisfactory solution 
can be successfully brought about. In view of this your committee 
deem it important to present at the outset a brief but clear statement of 
the reactions involved in the combustion of bituminous coal and their 
relation to the development and prevention of smoke. 

II. The Principles and Reactions Upon Which Combustion 

Depends. Conditions Favorable for Producing Smoke 

and Those Required to Prevent. 

All coals are composed ot an organic part which is a complex 
chemical combination of carbon, hydrogen, oxygen and nitrogen and 
an inorganic, or mineral, part, known as ash, consisting in the main of 
clay and minor quantities of iron and other impurities. Of the or¬ 
ganic matters carbon forms by far the larger part and nitrogen is pre¬ 
sent usually to the extent of not more than one, or one and a half per 
cent. 

Under a sufficiently elevated temperature carbon and hydrogen 
combine readily with the oxygen of the air thereby producing sensible 
heat The nitrogen is inert and merely plays the part of a diluent, 
while the oxygen in chemical combination with the other elements of 
the organic matter represents useful material already oxidized and 
therefore used up. When decomposition of the organic matter is 


4 


Prevention of Smoke. 


effected by the application of heat any two of the elements such as 
carbon and hydrogen or hydrogen and oxygen may separate from the 
general compound but heat is not developed because no chemical 
combination has taken place, but on the other hand heat is absorbed 
because a separation of these elements from the general combination 
has occurred. 

Besides the elements already referred to sulphur will be found to 
some extent in all coals and the greater part of this is usually present 
in combination with iron in the form of a distinct mineral of brassy 
yellow color, known as pyrites, which occurs mechanically associated 
with the coal. 

More or less moisture is always present in coal. When excessive 
this may be due to mine water or exposure to rain or snow after the 
shipment from the mine. Much of this moisture escapes on air drying 
but there always remains even after long air drying or in what appears 
to be perfectly dry coal, a notable quantity of moisture which in the 
ordinary bituminous coals coming to this market ranges from 5 to 10 
per cent This moisture can only be removed by exposing the coal to 
a temperature of at least 212 degrees F. 

The mineral matter or ash may include not only what might be 
called essential ash, that is, the mineral matter taken up by and form¬ 
ing a part of the plants from which the coal is derived, but may include 
also other and extraneous matter generally in the form of clay shale or 
slate occurring along the _planes of lamination of the coal. The slaty 
material can to some extent be removed by hand picking and very 
thoroughly by crushing and washing the coal, but the essential ash, 
which, however, is small in quantity and less injurious, must remain 
with the coal until the organic part is burned away. 

During combustion the particles of coal are more or less protected 
from exposure to the air and the grate bars become clogged by the 
ash, rendering combustion slow and irregular, while heating power is to 
some extent sacrificed in heating this inert matter. In these respects 
the evil increases with the quantity of ash. The fusibility, which de¬ 
pends upon the quality of the ash, is even more serious in its effects 
during the process of combustion. Oxide of iron if present in any 
considerable quantity would, by the formation of more fusible slags, 
increase the evil. Oxide of iron is derived mainly from the pyrites 
which loses its sulphur during the combustion ot the coal leaving the 
iron to oxidize and combine with the silicious clayey matter. Not 


Prevention of Smoke. 


5 


only is a very fusible slag thus easily formed but one that makes a 
very hard and clinging clinker. 

Turning now to the process of combustion it will be seen that 
when the coal is first charged into the already heated fire place the 
moisture and other volatile matter readily pass off leaving each lump of 
coal an incandescent mass of coke from which finally the glowing car¬ 
bon is removed by oxidation and the mineral matter or ash alone re¬ 
mains. This process, simple as it at first appears, is really very com¬ 
plex. 'I he moisture which may be evaporated at so low a temperature 
as 212 degrees F. does not necessarily pass off at once in the highly 
heated fire place before the other volatile matter is set free. The de¬ 
composition begins immediately on the outside of the lumps of coal 
and the volatile matter, and the moisture from adjacent parts escape 
together. Owing to the poor conducting power of the coal the heat 
travels but slowly to the interior of the lumps, so that for a considera¬ 
ble length of time after the coal has been charged it is giving off mois¬ 
ture with the conbustible volatile matter and thus diminishing the 
• temperature of combustion. When this moisture is present in very large 
amount as in lignite coals, containing from 12 to 20 per cent, its rapid 
escape induces a slacking of the coal which gives rise to serious loss 
from packing on the grate bars and the sifting of fine coal through the 
bars. That which is known as volatile matter is set free and escapes 
in the gaseous form as soon as decomposition of the coal is effected 
by the heat. The temperature at which this decomposition takes 
place varies with different kinds of coal. For bituminous coals it 
generally begins at about 250 degrees F , but of course is very slow at 
such a low temperature. The rate, also, at which the volatile matter 
is given off at any definite high temperature varies somewhat with dif¬ 
ferent coals as may be seen when treating coals in gas retorts. 

The composition of the volatile matter is very complex but it con¬ 
sists essentially of combined water and the hydrocarbons. The com¬ 
bined water is produced by the oxygen, which forms parts of the 
chemical combination of the organic matter of the coal, passing off 
with one-eighth of its weight of the hydrogen present. This, as before 
stated, does not represent oxidation performed during the combustion 
but simply elimination of the two, in these proportions, from the 
original organic compound. Heat is absorbed in this elimination and 
a further quantity of heat is sacrificed to raise this vaporized water as 
well as the moisture of the coal to the temperature of the furnace. 

The term hydrocarbon is applied to the complicated series of 


6 


Prevention of Smoke. 


organic compounds set free during decomposition. For present pur¬ 
poses these may be divided into three series which are clearly to be 
recognized while decomposition is in progress, whether brought about 
in closed retort or open fire place. These are: the light hydrocarbon 
or marsh gas series (CH 4 ) with three parts of carbon by weight to one 
of hydrogen; the heavy hydrocarbon or olefiant series (C 2 H 4 ) with six 
parts of carbon to one of hydrogen; and the asphalt or bitumen series 
which is too complicated to receive any definite formula but which 
contains still more carbon in proportion than in the olefiant series and 
also more or less oxygen. The marsh gas and olefiant series are 
gaseous forms of hydrocarbon, and the asphalt or bitumen the solid 
form which is more or less easily melted as the proportion of hydrogen 
is greater or less. 

Although called bituminous this class of coals contains no bitu¬ 
men. When decomposition takes place, however, under heat, com¬ 
pounds of the bituminous or asphaltic series are formed. The com¬ 
bined oxygen and one-eighth of its weight of hydrogen are set free as 
the combined water while the remaining or available hydrogen in com-, 
bination with more or less carbon forms the hydrocarbon series. 

The light and the heavy gaseous hydrocarbons volatilize in vary¬ 
ing proportions according to the composition of the coal. The light 
hydrocarbon burns with a pale non-luminous flame and with a maxi¬ 
mum effect of 23,500 heat units. Dissociation or separation of the 
hydrogen and carbon from combination with each other does not 
readily take place in this hydrocarbon and the products of its complete 
combustion are carbonic acid (C 0 2 ) and water (H 2 0 ). 1 

The heavy hydrocarbon is easily affected by heat and dissociation 
occurs at a red heat resulting in half of the carbon being set free 
leaving the gas as light hydrocarbon (C 2 H 4 = C + CH 4 ). It is this 
separated carbon in an incandescent state which in the main causes 
the luminosity of the flame when the heavy hydrocarbon is burned and 
it is this same separated carbon which makes the visible smoke 
when bitmniuous coal is burned. For the rapid combustion of this 
separated carbon not only is a strong oxidizing action necessary but a. 
very high temperature as well, probably not less than 2,000 degrees F. 

1 The term “Heat Unit”— H. U. also called “British Thermal Unit”—B. T. U. 
is the quantity of heat required to raise the temperature of one pound of water one 
degree Fahrenheit. To evaporate one pound of water of a temperature of 212 de¬ 
grees F. into steam of the same temperature requires nearly 966 H. U. 


Prevention of Smoke. 


7 


If this high temperature is not supplied in the fire place, where the 
gases are generated and the carbon separated, the latter will be car¬ 
ried along by the rapid draught and pass out unchanged as visible 
smoke. 

The conditions' which ordinarily prevail when this carbon is sep¬ 
arated are, it must be seen, quite unfavorable for its combustion. The 
coal is thrown into the fire place in cold lumps and generally in excess¬ 
ive quantities thereby interposing a comparatively cold and poor con¬ 
ducting layer between the glowing coals below and the gases rising from 
the fresh coal. Moreover while these hydrocarbon gases are being set 
free the moisture and the combined water, together amounting to from 
io to 20 per cent, of the whole weight of the coal, are passing off and 
absorbing a large quantity of the heat produced. The high tempera¬ 
ture required for the combustion of the separating carbon is therefore 
under these usual conditions impossible to attain. The quantity of 
air, too, which should at this stage of the operation be higher than at 
any other is either very much less, owing to the thicker bed of fuel on 
the grate, or if introduced above the grate, most commonly entejs 
directly through the firing door and is of low temperature. The heat, 
already comparatively low, is further reduced by this great volume of 
cold air, which having but little opportunity to mix with the gases, 
performs but imperfectly the duty for which it is admitted. Cold air 
and heated gases do not readily mix and the combustion of gases un¬ 
der such conditions is very imperfect. It is not surprising that under 
such conditions as these, much of the combustible gas reaches the 
chimney unburned and it is much less to be expected that any of the 
separated carbon should be consumed. 

Bitumen may be developed to such an extent during the combus¬ 
tion of some kinds of bituminous coals as to exude from the lumps, 
causing them to stick together and, as the heavy gaseous hydrocarbons 
are gradually distilled from this tarry asphalt a pitch coke remains 
firmly cementing the lumps and small fragment of coal into one large 
cake. This property of the “caking coals” adds to the evils already 
described. The grate becomes quickly clogged so that but little air 
can pass through, necessitating the frequent opening of the firing door 
and the use of a bar to break up the caked mass. Excessive quanti¬ 
ties of cold air rush in and the cloud of smoke from the chimney top 
appears, if possible, more dense than before. 

The coloring capacity of finely divided separated carbon is re¬ 
markably great, especially in the case of coals, which like most of ou r 


8 


Prevention of Smoke. 


western coals, yield in combustion large amounts of vapor of water 
from the high percentages of moisture contained and of combined 
water developed in combustion. That this carbon even from dense 
smoke represents but a small percentage of the weight of the coal may 
be shown by chemical examination. More direct proof has been fur¬ 
nished by the experiment of Mr. J. C. Hoadley, C. E., who passed 
through water all the gases from the flue of a boiler fired with bitu¬ 
minous coal producing a very black smoke, carefully collecting all the 
solid matter, drying and weighing. The amount of coal burned was 
12890 lbs., or about tons, every pound of which generated 25.23 lbs. 
of gases. The total weight of these gases was, therefore, 325215 lbs., 
or by volume 4263119 cubic feet. The whole quantity of solid mat¬ 
ter contained in this bulk of smoke gases was 42.63 lbs. or one-third 
of one per cent. No analysis was made of the solid residium collected 
but its gray color indicated that not more than half of it was carbon. 
From this it appears that the separated carbon, which made the smoke 
visible as a dense black cloud, represented only about one sixth of one 
per cent of the weight of the coal used , 

When coal is heated in a closed vessel or retort the moisture, 
combined water and hydrocarbons, being volatile, are driven off, but 
although heated to an intense white heat, if no air is admitted, there 
will remain the greater part of the total carbon. This part of the car¬ 
bon is consequently designated “fixed carbon” aud with the mineral 
matter of the coal constitutes what is called “coke.” A similar reac¬ 
tion takes place in the process of combustion in a fire place, except, that 
air being admitted, more or less of the fixed carbon is oxidized and 
passes off with the volatile matter in the gaseous form as carbon 
monoxide (CO) if one part of oxygen is taken up to one of carbon, and 
as carbon dioxide (C 0 2 ) if two parts of oxygen are taken up and the 
oxidation is thus complete. Lumps of coal may show, therefore, an 
exterior covering of coke, constantly increasing in thickness, in which 
the fixed carbon is burning with characteristic glow, while from the 
cracks and openings streams of the volatile gases are issuing giving a 
luminous flame terminating in streamers of smoke due to separated 
carbon. 

With the ordinary arrangements for admitting air to a fire place 
the conditions just described would add somewhat to the difficulties of 
of securing complete combustion. The carbon dioxide gas (C 0 2 ), re¬ 
sulting from the combustion of the fixed carbon surrounding the lumps, 
would rise and tend to envelope the hydrocarbon gases, escaping fiom 


Prevention of Smoke. 


9 


the interior, thus preventing sufficient access of air. Not only this, 
but the presence of carbon dioxide gas requires that more air be sup¬ 
plied to burn a given quantity of combustible than would otherwise be 
necessary. 

The bed of coke, which in time results after the elimination of the 
volatile matter, gives up its fixed carbon to complete combustion by 
means of two reactions. The air admitted at the grate gives up its 
oxygen, carbon dioxide gas (C 0 2 ) is formed in the lower layers of coke 
and this is more or less decomposed, according to the thickness 
of the bed, into carbon monoxide (C 0 2 -f C = 2CO). This 
carbon monoxide, meeting air admitted above the fuel bed, is 
burned again to carbon dixiode (2C0 + 20 = 2C0 2 ). In practice these 
reactions are but imperfectly carried out. No matter how thin the 
layer of fuel on the grate, provided the latter is completely covered, 
more or less carbon monoxide (CO) will be found to have passed 
above the bed. This is due to the fact that some of the carbon 
dioxide (C 0 2 ) formed at first is almost immediately reduced by con¬ 
tact with glowing carbon although there may be on the whole a large 
excess of air. The proportion of carbon monoxide (CO) increases 
and that of unconsumed air decreases with the thickness and com¬ 
pactness of the bed. 

The reduction of carbon monoxide (CO) is accompanied with a 
notable absorption of heat. With each unit of carbon monoxide (CO) 
so reduced 4325 units of heat are absorbed, or the carbon dioxide 
(C 0 2 ) generated by each unit of carbon if all reduced to carbon 
monoxide (CO), will cause the loss of 10093 out of 14544 units of 
heat. If this heat is not recovered by the burning of the carbon 
monoxide (CO) back again to carbon dioxide (C 0 2 ) above the fuel 
bed it is evident that less than one-third of the heat available will be 
utilized. 

In review of the facts presented it will be seen that for the com¬ 
plete combustion of bituminous coal including the separated carbon 
which forms the visible smoke, it is necessary that a very high tem¬ 
perature be constantly maintained in the fire place and that the air 
introduced for the combustion of the gases and free carbon above the 
fuel bed be in sufficient quantity, heated, and intimately mixed with 
the gases. It will also appear that with the fire place ordinarily em¬ 
ployed and especially when the fire is worked by the method so com • 
monly practiced, the conditions just mentioned are rarely attained. 




10 


Prevention of Smoke. 


III. The Fuels Used in St. Louis and Their Relations to the 
Smoke Problem. 

The fuels employed for various purposes in St. Louis and ap¬ 
proximate estimates of their consumption in 1891 are as follows: 


A. Illinois Bituminous Coal, 

B. Pittsburgh Bituminous Coal, - 

C. Gas House Coke, 2 

D. Other Coke Received part of which 

shipped beyond. Balance used in 
Smelting Furnaces, Foundry, Cupo¬ 
las, etc.,. 

E. Anthracite,. 

F. Gas,. 

G. Oil, 


2142126 tons. 
56000 “ 

36000 “ 


165000 “ 

60000 “ 

50000000 cu. ft. 


A. Bituminous coal is used to a a far greater extent than any 
other fuel, because of its comparative cheapness. The greater part of 
the State of Illinois is underlaid by workable seams of this coal and 
the coal producing area reaches within about eight miles of St. Louis. 
These coal seams lie comparatively near the surface, are quite undis¬ 
turbed while the overlying rocks make a good roof to work under and 
contain usually but little water. Mining can therefore be carried on 
at a low cost and owing to the open and generally level surface which 
characterizes Illinois, railroads are readily constructed and many of 
these traverse the coal regions and center here; all of which conditions 
favor competition in the production of coal and in its transportation to 
this market. 

It will be sufficient for the present discussion to classify the bitu¬ 
minous coal from the area deferred to as common Illinois coal, and 
coal from special districts, such as the Big Muddy, and other districts. 
The common Illinois coal comes for the most part from mines nearer 
the city. It is supplied at lower cost and is at the same time of in¬ 
ferior quality, being characterized by large percentages of moisture, 
ash and sulphur, comparatively low fixed carbon and large proportion 


2 The gas house coke here mentioned being a' product of the Pittsburg coal is 
necessarily contained in same; it represents very nearly the amount of fuel available 
for general use in the quantity of Pittsburg coal in the table of coal receipts. The 
balance being gas made out of same, tar and other by-products, and the losses in 
the processes of manufacture. 


Prevention of Smoke. 


i 


of volatile matter, which latter, aiso, contains much combined water. 
The heating power is, therefore, not high, usually about 10,000 heat 
units by calorimeter test, or a theoretical evaporating power from and 
at 212 degrees F. of about 10^ lbs. of water. The large amounts of 
moisture and combined water to be vaporized and heated to the tem¬ 
perature of the fire place cause a great absorption of heat and the 
large addition of waste gases from these sources leads to increased 
losses of heat carried off by the chimney gases. The tendency to coke 
somewhat during combustion makes it necessary to open the firing 
door often to loosen the bed of coal, while the large proportion of iron 
pyrites present readily causes the formation of hard clinker calling for 
frequent cleaning of the fire. For these reasons it will readily be un¬ 
derstood that the efficiency, that is, the percentage of the theoretical 
evaporating power utilized in practice, is not large. It is not too 
much to say that in the average boiler practice of this city the 
efficiency is considerably less than fifty per cent. This low efficiency 
is largely due to inferior boiler plants and reckless firing, but to the 
quality of the coal, outlined above, much is still chargeable. All these 
causes of low efficiency are very favorable to the development of 
smoky chimneys, as has been already explained, and the common 
Illinois coal may be regarded as the chief source of smoke in our city. 

Between the class of coal just described and the best type from 
Illinois, the Big Muddy, there are many grades and in so far as they 
have less of the objectionable and more of the favorable features, given 
above, the theoretical evaporating power is higher and the efficiency 
under similar conditions improved. The Big Muddy is a strong non¬ 
caking coal, rich in fixed carbon and comparatively low in moisture, 
ash and iron pyrites; the volatile matter contains but a moderate 
amount of combined water and is rich in gaseous hydrocarbons while 
but little of the asphaltic series is developed in combustion. The 
calorific value of this coal is about 12,000 heat units with a theoretical 
evaporation of about 12% lbs. of water from and at 212 degrees F. and 
the efficiency in good boiler plants should be 65%. It burns with a 
strong flame and although when carelessly fired or crowded into the 
fire place it yields richly in smoke, its characteristics are such that it 
can be made to show with proper handling as good a smoke record as 
any true bituminous coal. 

A small amount of block coal comes to this city from Indiana. 
Thus has the same general characteristics as the Big Muddy coal but 


12 


Prevention of Smoke. 


in a somewhat higher degree and is a favorable coal for yielding a good 
record if handled with care and skill. 

B. Anthracite or, as it is sometimes called “ hard cDal ” is too 
high priced in this market on account of the long haul from Eastern 
Pennsylvania, to be used for ordinary industrial purposes like boiler 
firing. Its main application is in heating furnaces, ranges, base burner 
stoves and to some extent in grates in domestic establishments. Owing 
to the fact that anthracite is mainly composed of fixed carbon with but 
an insignificant amount of volatile matter and that yielding no heavy 
hydrocarbons from which sooty carbon can be set free, il burns with 
but little flame and this is altogether smokeless. To the extent, there¬ 
fore that this class of coal is used in any city the atmosphere will be 
free from smoke. It is noticeable in New York, Boston and other 
eastern cities that formerly, when but little other fuel than anthracite 
was used, the atmosphere was clear and unobjectionable. In these 
days, however, with improved facilities for transporting to these cities 
the more distant bituminous coals, an increasing proportion of the 
latter is used and complaints of the growing smoke nuisance are more 
frequently heard. 

C. Coke is not only a smokeless but an almost flameless fuel since 
it is the residuum obtained by distilling off the volatile matter from 
bituminous coal. It is used to some extent in certain industrial opera¬ 
tions and might be employed to advantage for domestic purposes, if 
it was sold at prices properly proportioned to its fuel value. Gas house 
coke is porous and bulky, weighing less than half as much per bushel 
(36 lbs.) as bituminous coal and yet it is sold at a much higher rate 
(io-ii cents) per bushel than the coal. For these reasons it cannot 
be used for boiler and general industrial purposes and in other respects 
it is not well adapted. 

The coke brought to the city from a distance (mainly Pittsburg 
and the Connelsville district of Pa.) is a much harder and more com¬ 
pact coke than gas house coke. It is made in ovens constructed for 
the purpose and has been deprived almost entirely of the volatile 
matter so that it consists only of fixed carbon and ash. For these 
reasons it is less readily combustible than the more porous and bulky 
as well as less thoroughly coked gas house coke. The heating power 
is, however, much higher and it constitutes an admirable fuel for 
smelting ores, melting metals and other purposes where a strong con¬ 
centrated heat is required. This coke, costing $1.90 per ton at the 
ovens, is delivered here at a freight rate of $3.35 making the coke cost 


Prevention of Smoke. 


13 


$5 2 5 P er ton, while for gas house coke we are charged in St. Louis 
$5 00 per ton at the works. 

The neighboring Illinois coals are well adapted for making a grade 
of coke, which, while inferior to the Connelsville coke, for smelting iron 
ores, would be excellent for smelting lead ores and for many indnstrial 
pusposes as well as for special steam use as in locomotives. 

With modern systems of coal washing on a large scale the coal 
could be made very clean for a few cents per ton while special coking 
plants with provision for saving and marketing the tar and ammonia 
liquor should supply a satisfactory grade of coke superior to gas house 
coke and for a price which should not exceed $2.00 per ton. 3 

D. Gas consideied as a fuel includes: 

Natural Gas. 

Retort or Coal Gas 

Water Gas—Uncarburetted and Carburetted. 

Producer Gas. 

Natural gas is that obtained from gas springs or by boring into 
the rock strata. The conditions for supplying useful quantities of this 
gas are not present in this locality so that it is not available in the solu¬ 
tion of the smoke question for St. Louis, as it has been temporarily in 
Pittsburgh and other cities. 

Retort or Coal Gas is that ordinarily produced in gas works for 
illuminating purposes. It has a very high heating power and is used 
to some extent in domestic establishments in this city for cooking and 
and heating, also for a small number of gas engines. 

The above remarks apply also to water gas which is manufactured 
to some extent in St. Louis but used only as a fuel gas. In its uncar¬ 
buretted state it is much, and in its carbutetted, quite, inferior to coal 
gas in heating power. 

Producer gas is of far les sheating value than the other gases men 
tioned and is applicable to certain industrial operations where the con¬ 
ditions require and warrant the use of a special fuel clear of all im¬ 
purities and very readily controlled. 

None of these gases can be used to advantage for firing boilers 
since their cost for evaporating a given weight of water is much great- 

3 Some years ago an experiment was made in a large scale to show the fuel 
value of washed slack. The quantity tried was upwards of 60 tons. It was from a 
pile of Belleville slack which had lain in the open air for years. After washing, by 
which the slates, iron pyrites, and fireclay were removed, its fuel value was so me- 
what higher than Big Muddy coal. 


H 


Prevention of Smoke. 


er than when using coal by direct firing. This is contrary to public 
belief but it is none the less a fact and easily susceptible of proof as 
will be seen later in this report. Coal gas and water gas or possibly 
some form of producer gas will doubtless be used in increasing quan¬ 
tities in domestic establishments as the public learn how to use it 
properly and the gas companies learn how to economize in methods o^ 
manufacture and distribution and to be satisfied with smaller profits. 
The convenience, cleanliness and efficiency of gas, when properly used, 
for domestic purposes constitute advantages which more than counter¬ 
balance the real or fancied increased expense over coal directly ap¬ 
plied. The comparatively small consumption and intermittent charac¬ 
ter of most of the fuel requirements in households are especially favor¬ 
able to the application of gas. 

Oil is used to a limited extent in a few works for the heating of 
iron and steel where a clean, easily controlled heat is required. 

IV. The Various Classes of Fuel Users and their Relation to 

the Smoke Problem. 

The smoke nuisance in any large city like St. Louis may be traced 
to four general classes of fuel users: domestic fires, industrial furnaces, 
locomotives and boiler plants. 

Under the head of domestic fires may be included open grates, 
stoves, furnaces and ranges for heating or cooking, whether used in 
private houses, hotels or public institutions. In the abatement of the 
smoke nuisance this class is more difficult to deal with than any other 
for the reason that small quantities of fuel are burned at a time, in 
most cases slow combustion is required and excessive quantities of air 
are necessarily employed. The high temperature, therefore, so im¬ 
portant for the combustion of the separated carbon which causes the 
smoke, is not readily attainable. It may be said also that this class of 
fires is very commonly in charge of people quite ignorant of the first 
principals of combustion and not particularly noted for their appre¬ 
ciation of the advantage derived from the application of intelligent 
effort. Any material improvement in the use of bituminous coal with 
a view to reducing the smoke due to domestic fires is not to be ex¬ 
pected. The only complete solution of the problem so far as this class 
of smoke producers is concerned must be sought in the use of smoke¬ 
less fuels such as antharcite coal, coke and gas. 

The main objection, on the part of the public, to the more general 
adoption of these fuels in domestic establishments is doubtless the 


Prevention of Smoke. 


5 


question of cost. It is probable, however, that an exaggerated view is 
taken of this objection and that the time is not far distant when the 
general use of bituminous coal, as at present, in our households will 
hardly be justified even on the score of economy. Anthracite coal has 
for some years sold in St. Louis for a price about three times that of 
the bituminous coal employed in domestic establishments but it is not 
improbable that the relation of prices will in the not distant future be 
somewhat more favorable to the anthracite, owing to reduced rates of 
freight, improved methods of handling and storage on the part of coal 
and railroad companies and of combining to purchase in wholesale 
quantities on the part of consumers. The concentrated character of 
anthracite, its high heating power and the far higher efficiency with 
which it can be applied, as compared with bituminous coal, for such 
service as heating furnaces, base burner stoves and even cooking 
stoves and ranges where heavy duty and long hours are required, 
enable the careful consumer to realize results, in the way of improved 
service, economy in consumption and saving in labor and rapairs, which 
will be found to neutralize almost entirely even the present large dif¬ 
ference in price per ton. Already the use of anthracite prevails to a 
large and increasing extent in the establishments of those having 
abundant means, while the great variety of base burner stoves of simple 
design and comparatively low cost of recent development has led to 
the extensive use of this excellent fuel in the homes of those even in 
very moderate circumstances. 

For the ordinary operations of cooking, coke is admiraly adapted, 
being almost without flame and furnishing a strong glowing heat. 
Its efficiency in cooking operations is notably higher than that of bit¬ 
uminous coal as commonly used. It is a common practice with cooks 
after charging the stove and range with bituminous coal to reduce the 
latter to a glowing bed of coke before making much if auy use of the 
value on the fuel. With a large production of coke by gas and coke 
companies, more attention paid to quality and size, and with prices 
more nearly related to fuel value, the economical application of coke to 
ordinary cooking operations would compare very favorably with that 
of bituminous coal, and coke would doubtless soon become a favorite 
fuel in many households. 

A notable beginning has already been made in the application of 
coal gas and water gas to household cooking and heating. As stated 
above, gas has special advantages for the comparatively short and in¬ 
termittent service characteristic of many of the heat requirements of 


i6 


Prevention of Smoke. 


the household. These advantages are such that even at the compar¬ 
atively high prices at present prevailing the economy may with good 
management be placed on the side of gas as against bituminous coal. 

There were in use in this City for domestic service in the past two 
years, the following: 

No. of House Connections for 1890 1891. 

gas stove use. 1560 2385. 

One great difficulty in the use of gas is the ignorance prevailing 
concerning its use. The common practice at present seems to be to 
purchase the gas stove at a hardware establishment and notify the gas 
company to make the necessary connection. No attempt is made, ap¬ 
parently, by the Gas Co. to instruct the customer how to use the gas 
to the best advantage nor does the householder seem to take much in¬ 
terest in gaining the practical knowledge necessary to secure the most 
economical results. Too often it happens that to obtain more heat 
from a burner a larger quantity of gas is turned on when already the 
proportion of air admitted is insufficient. 4 

With increased experience in the use of anthracite, coke and gas, 
and with a more general diffusion of right information concerning the 
comforts and economies of living, ever larger proportions of bituminous 
coal will be replaced by these smokeless fuels in domestic consump¬ 
tion and thus a notable contribution will be made toward the clearing 
of our atmosphere. Fortunately, however, at present the domestic 
class of smoke producers is not the most objectionable. Though the 
chimney tops from which their contribution is made are the most 
abundant they are scattered over a great area and the quantity of 
smoke supplied by each is comparatively small and the more easily 
dissipated. This will be evident to any one comparing the atmosphere 
as regards smoke, on Sunday with that on week days. 

Industrial furnaces may be considered as those used in the various 
processes employed in metallurgical and manufacturing establish¬ 
ments. The operations performed in these furnaces are frequently not 
alone dependent upon the generation of heat but upon special reac 
tions which cannot easily be interfered with. Except in special cases 
they cannot be regarded as very objectionable smoke producers and 


4 When Natural Gas first came into general use in boiler furnaces in Pittsburgh 
dense black smoke was often caused by its imperfect combustion, until the right 
methods and quantities of air admission, fire brick checker work, etc., were found by 
practice. 


Prevention of Smoke. 


17 

the committee do not consider them of such importance in this con¬ 
nection as to call for immediate investigation, and action. 

Locomotives add very largely to the pollution of the atmosphere 
in this city because of their concentration in a few localities which are 
so disposed as to produce great volumes of smoke under certain 
meteorological conditions likely to intensify the effect. While in most 
of the important trafic centers the railroads arrive from many directions 
and operate in many parts of the city, in St. Louis there are only four 
localities where locomotives are very actively engaged: the old Mill 
Creek Valley, East St. Louis, the northeastern and southeastern parts 
of the City. In these places the switch engines, which are particularly 
offensive, are continually busy, while train engines at certain times of 
the day are also present in great numbers. When the wind is to any 
marked extent from the west but little if any annoyance is experienced 
from the smoke of locomotives, mainly because of their easterly loca¬ 
tion with reference to the Citv, but to some extent also on account of 
the dryness and buoyancy of our westerly winds An easterly wind 
on the other hand drives the smoke from these locomotive districts 
over the greater part of the City and, being usually laden with con¬ 
siderable moisture, favors the development of visible smoke and vapor 
as well as a tendency to hang heavily in the lower atmosphere. 

The remedy for this class of smoke producers must be sought in 
the use of a smokeless fuel like coke, especially for the switch engines. 
The neighboring Illinois coals can easily be made to furnish a satis¬ 
factory coke for such purposes and at comparatively low cost, if such a 
market were established for the coke and the ovens were arranged for 
utilizing the by-products, tar and ammonia liquor. 

The great offenders as smoke producers in this, as in every large 
city where the smoke nuisance prevails, are the boiler plants which 
continuously send forth volumes of black smoke from their tall chimney 
tops so that reasonable dilution is unattainable. The quantity of 
bituminous coal used, in the production of steam, forms a very import¬ 
ant part of the total coal consumption in this City and any marked 
success in the abatement of the smoke from this class of fuel users 
must furnish the key to the practical solution of the smoke problem. 

In dealing with this class of smoke producers it must be clearly 
understood at the outset that in St. Louis no assistance can be ex- 
p ected from the substitution of any of the smokeless fuels for bitumi- 
nous coal. Anthracite coal, coke and gas are all out of reach in the 
matter of cost when compared with our bituminous coal for all such 



18 


Prevention of Smokf. 


operations as steam raising where fuel economy is of paramount im¬ 
portance. Bituminous coal can be obtained for boiler purposes at a 
cost $1.25 per ton while anthracite is not likely, within an reasonable 
time to reach so low a figure as $5.00 per ton. Keeping these figures 
in mind and comparing the heat values and efficiencies of these fuels 
we have the following convincing exhibit: 


Heating Power, 
Theoretical Evaporation 
water per lb. of coal), 
Efficiency, 

Evaporation in Practice, 


Bit. Coal. 
(Common Illinois). 
9600 units. 

(lbs. of 

10 lbs. 

5 °%. 

5 lbs. 


Anthracite. 


13000 units. 

13.5 lbs. 

75 %- 
10 lbs. 


Two-tons of Common Illinois bituminous coal at $1 25 per ton 
($2.50) would therefore do the work of one ton of anthracite at $5.00. 
One hundred per cent greater cost for fuel than is necessary to do 
the work is certainly a much larger contribution to the solution 
of the smoke problem than the boiler users of St. Louis are likely to 
make. 

Coke as a fuel is far less adapted to stationary boilers work than 
anthracite and its price will never be such as to enable it to compete 
with bituminous coal for this class of duty even it it were in other 
respects suitable. 

The convenience and economy attending the use of natural gas in 
a number of localities in this country have led many people to believe 
that fuel gas, made from coal at large central stations, and distributed 
to factories and works, is the fuel of the future which will not only clear 
all chimneys but reduce all fuel bills as well. While it is unquestion 
ably true that fuel gas is especiall adapted for household use and will 
play an important part in the future for such use, it is equally true that 
as a fuel for raising steam it can never compete in the matter of 
economy with coal directly applied. At several establishments where 
gas is employed for certain industrial heat requirements attempts have 
been made to use the gas under boilers; at first glowing reports were 
circulated indicating a saving over coal cf 20% and even 33 l /s%* A 
little experience has always shown, however, not only that such re¬ 
sults are not attained but that the cost of the gaseous fuel is so much 
in excess of coal used directly as to make it necessary to return to the 
latter system. 


Prevention of Smoke. 


19 


The following simple calculation will serve to show the uselessness 
of all attempts to convert bituminous coal into gas and distribute it to 
boiler plants. 

The average quality of fuel gas made from a trial run of several 
car-loads of Illinois coal in a well designed fuel gas plant showed a 
calorific value of 243391 heat units per 1000 cu. ft. of gas or 10105- 
594 heat units per ton of coal. This is equivalent to 5052 8 heat units 
per pound of coal, whereas by direct calorimeter test an average sample 
of the coal gave 11172 6 heat units, or an efficiency of 45.2%. 

1 pound of the coal by direct application showed a theoretical 
evaporation of 11.56 lbs. water. 

The gas from one lb of the coal showed a theoretical evaporation 
of 5 23 lbs. water. 

48.17 pounds of the coal were required to furnish 1000 ft. of the 

gas. 

Taking the efficiency in the use of the coal direct at 50%, 

Taking the efficiency in the use of the gas direct at 90%, 

Taking the cost of the coal at 6 cts. per bushel, 

Taking the cost of the gas at 8 cts. per 1000 cu. ft, 

We have as the cost of evaporating 1000 lbs. of water by coal 
directly applied: 

5 %oo of 11-56=5.78 lbs. of water to be evaporated in practice by 
1 lb. coal. 

100 % 78 =l 73 lbs coal to evaporate 1000 lbs. of water; 173 lbs. 
coal at 6 cts. per bushel=i3 cents, and as the cost of the same coal 
converted into gas and applied, 

9 %oo of 5.23=471 lbs. of water to be evaporated in practice by 
gas from one pound of coal. 

l000 /i-7i = 212.3 ^s. coal required=44oo cu. ft. of gas; 4400 cu. ft. 
of gas at 8 cts. per 1000=35.2 cents. 

It will be observed that the conditions assumed are especially 
favorable to the gas, the cost being placed at the remarkably low figure 
of 8 cts. per 1000 cu. ft. which is about the actual cost of manufacture 
and distribution upon a large scale, and a very high efficiency is taken. 
Notwithstanding all this the coal used directly shows an advantage of 
over 170%. 

For fuel purposes two kinds of oil are used, crude pretoleum, 
usually from Lima, O., and residuum after distilling off the lighter oils. 

The Lima crude pretoleum oil comes to this market in tank cars 
holding 6000 gallons. The price is 1.8 cents per gallon, to which must 


20 


Prevention of Smoke. 


be added $5.00 per car for switching, etc. Even under favorable con¬ 
ditions, therefore, as to location of boiler plant, the cost of this oil de¬ 
livered to the boiler will be at least 2 cents per gallon. A gallon of 
this oil weighs 6.9 lbs. The theoretical heat value of this oil is about 
20,000 heat units, equivalent to a theoretical evaporation of 20 7 lbs. 
ot water. Assuming an efficiency of 80%,.the evaporation in practice 
would be 16.56 lbs. of water per lb. of oil. The cost of evaporating 
1000 lbs. of water would therefore be 17.54 cents. With a bituminous 
coal giving an evaporation in practice of 5 lbs. of water per lb. of coal 
and costing $1.25 per ton the same work could be done for 12.5 cts. a 
difference in favor of the coal of 40.32%. It will be observed also 
that the conditions assumed in this calculation are especially favorable 
to the oil. 

The -‘fuel oil” or ‘‘residuum” weighs about 7 3 lbs. per gallon 
and has a calorific power of 16880 or a theoretical evaporation of 
17 47 lbs. of water per lb. of oil At 3 cents a gallon and under the 
conditions assumed above the cost of evaporating 1000 lbs. of water 
would be 29.28 cents or 134% more than when using the coal. 

It is evident, therefore, that the only fuel likely to be used to any 
extent for boiler work in and about St Louis is bituminous coal, and 
of a quality, as has aiready been explained, highly conducive to the 
production of abundant smoke when undergoing combustion. To 
secure a reasonable abatement of smoke under these conditions is the 
main problem requiring solution, and there are special difficulties 
attending it. In the vast majority of boiler plants of this city, the 
boilers are taxed, if not continuously at least an important part of the 
time, much beyond their capacity to furnish the steam demanded of 
them when consuming the limited amount of coal required for a good 
smoke record. In order to supply the additional power, therefore, ex¬ 
cessive amounts of coal must be burned in a given time and under the 
ordinary conditions of combustion dense clouds of black smoke are 
sure to result. In those cases where the boiler capacity is ample and 
the service comparatively light and uniform, as in running a few eleva¬ 
tors, a small number of incandescent lights or serving a steam heating 
system, it is not a difficult matter, with ordinary care in firing, to pre¬ 
serve a reasonable smoke record. The real problem is to burn large 
quantities of coal with comparatively smokeless combustion in a limited 
space with sudden and enormous changes in the demand which the 
firemen himself is unable to foresee and of which no notice can be 
given him. Careful tests in a manufacturing establishment have showm 


Prevention of Smoke. 


21 


jumps of one hundred per cent within an hour in the demand for steam 
varying from a little under the normal work of the boiler to eighty per 
cent above it. Such sudden and excessive demands must be met by 
the stoker with his energies strained to a point where all other questions 
or considerations must give way before his supreme effort to hold the 
pointer on the steam guage up to the necessary pressure as long as the 
demands continue. It is impracticable to time these suddenly in¬ 
creased demands so that the fireman may have fifteen minutes warning. 
Again, the chaiacter of the materials operated upon may change. 
Machinery will become deranged and worn, neglect at one point com¬ 
pels increased effort at another, a bad lot of coal comes in or the fires 
are dirty and clogged; the draft may be affected by a change in the di¬ 
rection and force of the wind, in the barometric pressure or in the 
temperature of the air. These things may happen singly or they may 
accumulate, but the work must go on and the fireman is obliged to throw 
in coal enough to keep everything moving; for in the boiler plant the 
latent energy of the coal is transformed into mechanical power, and 
this is the source of all the various manifestations of force which are 
combined and utilized in the many processess of modern manufacture. 
These contingencies constantly arise in rolling mills, flour mills, tobacco 
works, breweries, distilleries, electric light stations, cable and electric 
power stations, etc. To burn coal to the best advantage under all 
these varying conditions, where the boiler plant and the hard worked 
stokers are called upon to equalize all these differences, and the hand 
on the steam guage relentlessly registers the fact, is quite a different 
problem from burning a limited amount of coal steadily during a given 
time. 

It maybe urged that most of these conditions may be met by an 
increase in the boiler plant. This is true to a certain extent but it is 
often not possible to find room for more boilers. In many instances 
it would be necessary to take down needed machinery and remove it 
to other points The relative position of one machine to another is 
often such that a change may disturb the whole process of manufac¬ 
ture. Additional boiler power generally calls for additional chimney 
Capacity and there may not be room for that. It is in rare-cases that 
the addition of even fifteen or twenty per cent to the boiler power of 
an establishment can be accomplished with only a proportionate ex 
penditure. There are many works in this city where not ten square 
feet of room can be found for an increase of boiler power. 


22 


Prevention of Smoke. 


V The Conditions Under Which Fuel is Consumed in Boiler 

Plants in St. Louis. 

The difficulty of getting accurate and reliable information from 
the steam users of this city, concerning plant and practice, has been 
the cause of serious annoyance and hindrance to your Committee. 
There are few subjects apparently which are surrounded with so much 
unnecessary mystery or on which so little definite and accurate 
knowledge is obtainable. Many steam users go on from year to year 
without even an approximate idea of the amount of work their boiler 
plants are doing. Most of them know their annual consumption of 
fuel and can tell from their water tax receipts the total amount of w'ater 
used in their works, but how much of this is converted into and used 
as steam is seldom estimated with any approximation to the real facts. 
Steam users are generally content with some arbitrary classification of 
their boilers such as 50 H.P., 100 H.P., etc. Such classification is 
usually based upon an empyrical assumption of a certain number of 
square feet of heating surface for a horse power. This is, however, a 
well established basis of computation, recognized among engineers, 
which fixes a horse power as the amont of steam obtained from the 
evaporation of 30 lbs. of water per hour. Many boilers classed as 
100 H.P. run at only 75 to 90 H.P., and even less, while others 
of the same rating are pushed to 130 and 150 H.P. Thus we have 
a variation from 30% below to 50% above the normal capacity of the 
boilers. 

In most cities os the Mississippi Valley, the boiler practice still 
bears the marks of having originated on the river. Gn steamboats 
the necessity of the situation required that a great deal of work should 
be done with comparatively light and therefore small boilers. In St. 
Louis our engine practice for many yeu:s followed that of the river in 
spite of entirely different conditions, and in the same way our land 
boiler practice has but gradually developed on its own legitimate lines. 
We find, therefore, that as a rule the standard horizontal tubular boilers 
are pushed to a much higher performance both in quantity and pres¬ 
sure of steam than is usual in land practice east of the Alleghenies, 
and this in spite of the fact that we have to do this pushing with a fuel 
far inferior to that used in the East. We have, therefore, doubly in¬ 
creased the difficulty so far as smokeless combustion is concerned. 
First, we have a coal which will make far more smoke than the anthra¬ 
cite semi bi’.uminous or even the bituminous coals, of the large manu 


Prevention of Smoke. 


facturing districts on the eastern slope, and, then while we have to use 
2 5 % to 50% more of it to get the same effect, we have been adding 
40% or 50% to the work to de done by the same boiler, and hence in 
the same limit of space 

In attempting to get some reasonably approximate estimate of 
the average conditions and work of the boilers in this city the Com¬ 
mittee with the sanction and assistance of the Mayor, addressed to all 
steam users a circular (a copy of which is presented herewith, see 
Appendix I.) asking eight plain, practical questions. These circulars, 
to the number of over eleven hundred, were sent out by the City Boiler 
Inspector, with the request that they be returned with as clear and 
accurate answers to the questions as possible. Only seventy-eight, 
less than 7 per cent were returned with any attempt to answer the 
questions and not one of these could be regarded as a satisfactory 
statement of the information asked for. 

There were 78 reports made in all. As some especially requested 
their names to be withheld, we thought it but fair to mention no one. 
Out of these, seven were using Smoke Preventing Devices. 

One of these gets less steam out of each pound of Big Muddy 
coal, than the average of good local practice shows for common Belle¬ 
ville Coal. 

A second is perfectly satisfied, but he is using Big Muddy coal. A 
visit to his works by two members of the committee show T ed the remark 
able fact that with the device in action the smoke disappeared in two 
minutes after firing, while when the device was shut off the smoke 
ceased in one and a half minutes. 

A third reports heavy work, but as he has his own smoke pre 
venting device, his testimony is naturally that of a party in interest. 

A fourth reports favorably on the divice used, but we found his 
work by data given us on the spot by the man in charge to be 35 per 
cent below the ordinary rated capacity of such boilers, or say about 
60 per cent below the work frequently required of them in manufactur¬ 
ing plants 

A fifth reports favorably on device used, but the work of the 
boilers was found to be very light. 

A sixth has since thrown out the device as fuel wasting. 

A seventh reports satisfactory results but the work is evidently 
very light. 

Nineteen have used various kinds of smoke preventors but have 
thrown them out for various reasons Of these one has spent about 


24 


Prevention of Smoke. 


$8000; another $3000 on unsatisfactory experiments; a third found 
his “smoke consumer” consuming one-eighth more coal than the com¬ 
mon furnace. 

As coal consumption per square foot of grate per hour, the table 
shows a minimum of 7.5 lbs., a maximum of 31.2 lbs., and an average 
of 16.1 lbs. These figures alone suffice to show that in regard to 
smoke preventing devices “what is one man’s meat” will prove “an¬ 
other man’s poison.” 

In most of the plants reported on, the smoke continues more than 
5 minutes immediately after firing. Since firing has to be done about 
every 15 or 20 minutes, it follows that when four or more boilers use 
one and the same chimney the smoke will be practically continuous. 
If the practice were lu charge all furnaces simultaneously, the whole of 
this smoke would appear at once, while the total quantity would not 
vary at all. 

As to the distance from grate to boiler, which has a direct influ¬ 
ence on the production of smoke: 

31 have 18" and under, which may be considered as bad practice. 

23 have between 18" and 24", which is fair practice. 

21 have 24" and over, which is good practice. 

Twenty two plants have no margin of power at all; 12 have 25% 
margin or less; 27 have more than 25%. 

It appears therefore from the table that less than 45 out of 100 
of the steam plants in St. Louis could make use of the general run of 
“Smoke Consumers” without risk of shutting down. And out of these 
45 probably one-half would find their limits drawn so close as to com¬ 
pel them to discontinue their use after a short trial. 


VI. Requirements Necessary for a Successful Smoke Pre¬ 
venting Device. 

To prove successful under the conditions, which, as outlined 
above commonly exist in the boiler practice of this city, a smoke pre¬ 
venting device must satisfy three sets of requirements: 

I. Efficiency .—This includes (a) the development of such a high 
temperature and oxidizing action as to insure the combustion of the 
free or separated carbon which forms the visible smoke; (b) regularity 
of aciion under varying conditions such as are induced by charging 
fresh coal, cleaning fires, inattention of firemen, etc.; (c) not suscepta- 
ble to derangement under conditions likely to obtain, as carelessness 


Peevention of Smoke. 


25 


of fireman inferior water, bad clinker, etc.; (d) small, if any increase 
in the cost of operating. 

II. Capacity .—This must be such that efficient action will be 
secured not only when the boiler is working up to its full rated capacity, 
but even when forced in order to meet extraordinary demands. 

III. General Applicability .—Under this head may be included 
(a) ready adjustment to all forms of boilers and boiler settings; (b) ap¬ 
plication where space is already limited; (c) comparative low first cost; 
(d) repairs, small in amount, easily made and of low cost; (e) operation 
without injury to boiler or other accessories. 

It is hardly necessary to add anything explanatory of the above 
statement. In view of what has already been given showing the con¬ 
ditions relating to boiler practice in St. Louis and concerning the re¬ 
actions involved in combustion and the prevention of smoke, these re¬ 
quirements should be self-evident and considered all important. 

Of the almost countless number of devices proposed there are few 
indeed incapable of showing good smoke results under special con¬ 
ditions. Those having decided merits (and there are many of these) 
are capable of successful operation when the conditions are generally 
favorable. The severe test and which very few are able to pass is that 
of capacity. With a fuel consumption up to 18 to 20 pounds of coal 
per square foot of grate per hour the better devices are able to show a 
good smoke record but to the extent to which combustion is pushed 
beyond these limits the chimneys return to their evil ways of polluting 
the air. The importance of this capacity test will be appreciated when 
it is understood that in the majority of boiler plants of this city the 
limits of fuel consumption, stated above, are greatly exceeded during an 
important part, if not the whole time, of their operation. It is not at 
all uncommon to find boilers in this city forced to the extent of burn¬ 
ing 30 lbs. of coal per square foot of grate per hour. 5 Finally, it may 
be stated, without fear of successful contradiction, that not one of the 

5 On March 10th, 1888, Mr. C. E. Jones of our Committee and Mr. Chas. F. 
White, recently appointed Smoke Inspector for the Citizens Committee in Chicago, 
made a report to Mr. N. O. Nelson, of the City Council, on Smoke preventing 
furnaces. 

The heaviest loss by carbonic oxide gas escaping unconsumed was less than 
one per cent. 

The results of 39 careful tes’s are tabulated. The smoke preventing furnaces 
on the average showed only 74 per cent of the capacity of the common furnaces in 
burning coal, they reduced the work of the boilers 28 per cent, and they required 
about 2 per cent more fuel to do the same work. 


26 


Prevention of Smoke. 


devices so far brought forward is capable, in its present form and ap¬ 
plication, of fully meeting and satisfying all the requirements specified 
above 

VII. Classification of the Important Types o£ Smoke Prevent¬ 
ing Devices already Proposed, and the Principles upon 

which they Depend. 

It would be manifestly impossible to give in a report like this even 
a brief description of each of the many devices which have been in¬ 
troduced at various times for the purpose of preventing the escape of 
smoke. To mention each by name, and state its merits and defects, 
would be so incomplete a presentation of the case as might lead to 
misunderstanding and perhaps injustice. It seems wiser, therefore, to 
attempt only a general classification of the more important types and 
discuss the principles upon which their action depends, so that a clear 
understanding may be obtained of their limitations and of the outlook 
for the future. 

A. Stecwi Jets .—These consist of steam injectors to force air into 
the fire place either directly from the outside or after being heated. 
They have been applied in many ways and have been called by many 
names. The action is essentially the same in each whether the nozzles 
are placed in front above the file doors, in the side walls of the fire 
place, or in the bridge wall. It is to supply air in sufficient quantity 
above the fuel bed for the combustion of all combustable material and 
to effect such a thorough mingling of the air, gase* and carbon that 
combustion will take place more readily, and hence not far beyond the 
fire place. Where the heat is sufficient more or less water gas is form¬ 
ed by the decomposition of the steam into hydrogen and oxygen, the 
latter in a nascent state being more effective in oxidizing the separated 
carbon and the former readily burning back to water by combination 
with the oxygen of the air blown in. 

'These jets can be made to work satisfactorily where the demand 
upon the boiler is comparatively light and does not vary much but it is 
necessary to supplement their action with careful and regular firing. 
If too much coal is charged in the fire place at a time the temperature 
is likely to be so much reduced that the action of the jets tends to re¬ 
tard rather than promote combustion. With variation in the demands 
upon the boiler the jets require corresponding adjustment to secure 
tavorable results. Such a system is, therefore, largely dependent for 


Prevention of Smoke. 


27 


its successful operation upon the skill and faithfulness of the fireman. 
In most instances the capacity of the jet blowers is too small for the 
amount of work the boilers are called upon to do and where the ca¬ 
pacity is sufficient it often happens that with the careless handling 
usually practiced the amount of steam used in the jets more than off¬ 
sets any gain in efficiency due to improved combustion. 6 Another 
very important consideration is the setting and adjustment of the noz¬ 
zles, which, it not very carefully attended to, may be the cause of a 
blow pipe action upon the boiler shell or grate bars resulting in a rapid 
burning of the metal especially from the strong oxidizing action of the 
decomposing steam. Several instances of this kind have occurred in 
this city. 

It will be evident, therefore, that the steam jet blower system as 
usually applied and operated, is far from satisfying the requirements 
specified for a successful device. The determination of capacity and 
the adjustment in setting cannot safely be left to the boiler maker or 
boiler setter, nor to the engineer of the establishment, who is frequently 
only an engine tender. Nor can the operating of the device be left to 
the average fireman. On the other hand it may be said that the re¬ 
quisite engineering skill and experience can always be obtaine 1 if 
sought for to secure a safe and suitable application of the systen. The 
necessary qualities to make a reliable fireman can also be had if those 
interested would appreciate the importance and advantage of demand¬ 
ing these and of offering suitable compensation of faithful and efficient 
services. Under such conditions the steam jet system can undoubt¬ 
edly be made to yield satisfactory results in controlling the smoke, 
especially where the boiler capacity is ample for the requirements and 
where the service is not too variable. These results can be attained, 
too, without injury to plant but not without some increase in the cost 
of operating. (See Appendix II.) 

B. Firebrick Arches or Checker Work .—These have been ap¬ 
plied in many ways and the resulting devices are known by many 
names. They are usually placed near the rear end of the fire place or 
over the bridge well. Their action is of a twofold character; first, to 
cause a more thorough mingling of the smoke and gases with air ad 
mitted above the fire bed, and second, to increase the heat of this 


e At the Home Cotton Mills some years ago, steam jets over the fire were tried 
as smoke preventors. The result was an increase of 12 per cent in the fuel con¬ 
sumption for the same w^rk. 


28 


Prevention of Smoke. 


mixture. The conditions favoring complete combustion, not only of 
the gases but of the more difficult combustible separated carbon at the 
same time, are thus brought about. 

The arch causes the smoke, gases, and air to pass through a con¬ 
stricted passage close to the fuel bed which should be kept in the 
glowing coke stage. The arch itself serves not only to reflect the 
heat from the fuel bed but as a storage accumulator of heat which 
tends to regulate the heat and keep it up to a more uniformly high 
temperature. 

The checker work is intended to produce the same result but in a 
slightly different way by dividing the general volume of smoke and 
gases into a number of small currents and causing more intimate con¬ 
tact with the firebrick surfaces. 

So far as disposing of the smoke is concerned these appliances 
can be made to produce good results with careful firing. Their 
capacity in this respect is, however, comparatively limited being de¬ 
pendent upon the proportion of heating surface to the volume of gases 
and smoke to be heated and also upon the proper alternation of clear 
combustion, which supplies the heat to the storage surfaces, with the 
fresh coal firing which calls for the heat stored up. Another and 
more serious objection is their want of durability, and hence compara¬ 
tively high cost due not only to the actual repairs, but to the interfer¬ 
ence with regular operations as well. Devices of this character can¬ 
not, therefore, be regarded as affording a satisfactory solution of the 
smoke problem. (See Appendix III.) 

C. Hollow Walls for Preheating Air .—A number of patents have 
been taken out based upon this system but they are all likely to lall 
short of satisfying the requirements specified. With careful firing in 
boilers performing moderate and uniform duty this, system favors more 
complete combustion above the fuel bed by supplying heated air 
through a number of small holes or slits in the walls of the fire place 
and and the bridge. It need scarcely be pointed out, however, that 
the capacity must be too limited to make its application to our boiler 
service of any material advantage. Other and well founded objections 
are that flues in the walls of a boiler setting are likely to make the 
construction less stable and durable. The openings, also, for the ad 
mission of air to the fireplace, readily become clogged and suffer from 
the ignorant and unfaithful labor frequently found in boiler service. 

D. Coking Arches or Chambers .—This system is a favorite one 
with many inventors of smoke preventing devices. It consists in con- 


Prevention of Smoke. 


29 


structing a chamber in front of, or in an arch over, the forward part of 
the fireplace where the fresh coal is charged and retained until the 
greater part of the volatile matter is drawn off. The resulting coke is 
then pushed to the rear to serve as the hot bed over which the vola¬ 
tile matter from the fresh coal in front is made to pass. These de¬ 
vices are intended to accomplish more fully what is aimed at in the 
system of firing in an ordinary fireplace known as coke firing, which 
consists in firing in thin layers and small quantities at a time over the 
forward part of the grate and keeping the strong, clean heat of the 
glowing coke near the bridge wall. 

For disposing of smoke these devices are effective only so far as 
the fireman is careful in working the fire and the amount of coal to be 
burned in a given time is limited. The use of arches, etc., in the fire¬ 
place is open to the objection that such constructions are necessarily 
short-lived, exposed as they are to high heats, changing temperature, 
and fluxing ashes. 

E. Double Ccmbustion .—Applications of this system have been 
attempted in many ways. Some have taken the form of duplicate 
fireplaces whieh are charged with fresh coal alternately. Suitable 
dampers or valves cause the smoke and gases from the freshly charged 
grate to pass beneath and thence through the other fire bed, which 
consists in the main of glowing coke. In other cases there is but a 
sfngle fireplace, a portion of the smoke and gases being drawn by 
means of a fan blower from the breeching after having passed the 
boiler and forced under the grate to be passed through the fire bed a 
second time. 

It is clear that in passing such a large proportion of useless gases 
through a fire bed much of the air needed for combustion will be 
crowded out and heat will be absorbed in raising the temperature of 
these useless gases to that of the furnace. The double furnace re¬ 
quires extra room and the single furnace a fan blower and both require 
more skill and attention than can be expected of the average fireman. 
Those applications of this system that have been tried have generally 
proved short lived. 

F. Downward Draught-Furnaces .—These have been applied in 
a variety of forms and under various patents for a number of years. 
They consist essentially of a fireplace with the back closed so that 
there is no direct communicatiou for the smoke and gases to pass 
away under the boiler except downward thiough the fire bed. The 
closed back is formed either of a water leg from the boiler which 


Prevention of Smoke. 


30 

passes below the level of the grate or a drum set below the level of 
the grate and connected at either end with the boiler by tubes, the 
space between the drum and the bottom of the boiler shell being 
bricked in, solid. Owing to the intense heat upon the grate, it is 
necessary to substitute a water tube grate for the ordinary bars and 
these water tubes are connected at the back with the water leg or 
drum; at the front, by means of headers and connecting tubes, with the 
boiler shell. All these parts, therefore, belong to the water circulating 
system of the boiler and supply so much additional heating surface. 

The combustion of the fuel is effected, by such a device, in a far 
more rational way than on the ordinary fire bed. The fresh coal is as 
usual charged on the top of the bed but the air enters from the top 
and therefore cooler part, quickly gaining heat from contact with the 
heated coal and passes with the smoke and distilling volatile matter 
through the bed of incandescent coke below. 

The separated carbon and all gaseous products thus become in¬ 
tensely heated. The moisture of the coal and the combined water of 
the volatile matter are decomposed into hydrogen and carbon 
monoxide gases which, with the aid of additional air supplied below 
the grate, burn with useful effect while the separated carbon disap¬ 
pears into invisible carbon dioxide gas. 

In order to get the requisite amount of opening for draft the water 
tubes forming the grate must be spaced at greater distance apart than 
is the case with ordinary grate bars. Some of the fuel will, therefore, 
drop through, impelled by the force of the draft added to that of gravity. 
With caking coals such as most of our Illinois coal the loss from this 
source is not great under moderate firing. When, however, the fires 
are pushed and frequently worked with a bar to loosen the mass of 
coke or to clean the grate considerable coke falls through. This has 
led to the adoption of an auxiliary grate of ordinary typb set some dis¬ 
tance below and through this all the air is delivered for the combus¬ 
tion of the gases issuing below the upper grate. As the lower grate 
receives only the incandescent fuel falling from above the space be¬ 
tween the two grates is in a favorable condition for completing the 
combustion, being highly heated and supplied with heated air. 

Such a system is well adapted to insure a good smoke record even 
when the fire is forced and to a large extent with careless firing. It 
has the advantage also ot being readily attached to a variety of boilers 
and such attachment serves to increase the heating surface and hence 
the capacity of the boiler. 


Prevention of Smoke. 


3i 


The objections to this type of smoke preventing device, in any 
form in which it has been presented, arise mainly from defects in con¬ 
struction which although more or less serious can be overcome. The 
arrangement for admitting air for the lower grate through the floor 
plates in front of the boiler is defective, in that it does not permit of 
control oi the air current. Excessive quantities of air enter, causing 
unnecessary waste of heat and a lowering of efficiency. The water- 
tubes of the grate and the connecting pipes are liable to unusual 
strains at the joints and these latter are not altogether reliable. The 
water-leg or drum, which acts as an inverted bridge is subjected to in¬ 
tense heat as are also the tubes of the water-grate. Unless our St. 
Louis water is purified, scale will have a tendency to deposit at such 
places, especially on the lower surface of the water-leg or drum when¬ 
ever there is any imperfect circulation. Any marked deposit of scale 
on these surfaces would cause the metal to burn rapidly and give way. 
While serious difficulties have not resulted to any great extent from 
these defects there is always more or less danger especially where 
higher pressures are carried, and these defects should be overcome 
before the system can receive unqualified approval. 

In many boiler plants in this city, it would be difficult to apply this 
system owing to the lack of necessary space. A distance of two feet 
would be required between boilers or pairs of boilers to permit of 
cleaning the water-leg or drum. It is necessary also to have a greater 
depth of 18" to 24". Noth withstanding these various objections the 
system has so many valuable features that it gives great promise for 
the future and is well-worth the attention and study required to secure 
the needed improvements, and adapt it to the exacting conditions of 
our local boiler practice. 

G. Automatic Stokers. There is a great variety of these devices, 
some of which a’e applied independently and others as auxiliaries to 
other types of smoke preventing devices. The principle involved in 
their operation is to secure regular and uniform feeding of coal to the 
fireplace by mechanical action in place of the irregular and unreliable 
service of the ordinary fireman. The mechanical action may be applied 
in the form of screw or hopper feeders to fixed inclined grates or to mov¬ 
able inclined or step grates. Most of these require the coal to be 
sized to nut, pea or slack grades and but few are capable of handling 
to advantage lump coal, or “the run of the mine.” The coal when 
properly sized is fed with great regularity, thus doing away with the 
periods of heavy smoke development and clear firing. The gas and 


32 


Preaention of Smoke. 


smoke are therefore distilled from the coal uniformly and near the 
upper or forward part ot the grate changing the fuel to incandescent 
coke as it approaches the lower end of the grate. 

While automatic stokers are capable of giving good results under 
favorable conditions their limitations are such that they cannot be re¬ 
garded as applicable to any important extent for the boiler service of 
St. Louis. They require that a coal be used which does not readily 
cake and does not cliinker to any serious extent. The boiler must be 
of ample capacity, also, so that no forcing is required. When, as is so 

generally the case here, a boiler is forced, the tendency of the coal to 

cake and clinker is very greatly increased. The moving grate bars 
often fail to prevent caking and the clinker is liable to choke the bars 
and impede their action. To clean a fire by hand where an inclined 
or a step grate is used is a very laborious and tedious undertaking for 
the fireman and he is too apt to shirk it or perform it inefficiently. 
Another limitation lies in the fact that although automatic stokers are 
provided with devices for varying their speed, they cannot act as 

promptly nor follow the variations in demand as closely as the fireman 

with shovel and slice bar. With our caking and hard clinkering coals 
and overworked boiler plants, any system with such limitations is likely 
to prove worse than useless, as a device to diminish smoke or econo¬ 
mize fuel 

The fact must not be lost sight of that in using any form of smoke 
preventing device, greater care must be exercised in the examination 
of the boiler and that more frequent cleaning of the interior is re 
quired. The better the combustion and the higher and more concen¬ 
trated the heat resulting from this, the greater the danger of over-heat¬ 
ing and burning the portions of the boiler heating surface on which 
mud or scale may lodge. It is well known that mud and scale will 
more readily settle on those portions of the furnace sheets receiving 
the most direct action of the flame, since rising currents will always 
be established there inducing return currents from other portions of 
the boiler which sweep scale and mud and all suspended impurities 
to these points. In those devices, in which danger points are covered or 
obscured from the eye of the fireman or engineer, the danger is of course 
increased. Boilers of inferior design, imperfect in construction, or de¬ 
fective to any extent in circulating action, will be rendered less secure by 
the application of any such devices as promote more efficient combus¬ 
tion. Your Committee therefore inclines to the belief that, before a 
general adoption of these devices, the use of a simple but effective sys- 


Prevention of Smoke. 


33 

tem of purifying the feed water before it enters the boiler will be 
necessary. 

VIII. Experiences in Other Cities relating to the of Abate¬ 
ment of the Smoke Nuisance. 

Pittsburgh, although possessing steam coals capable of nearly 
50% greater economy in boiler furnaces, than our standard fuels, was 
long known as the Smoky City. She succeeded in temporarily clear¬ 
ing her atmosphere by the use of Natural Gas, but is now rapidly re¬ 
lapsing into her former state. 

The City Councils of Allegheny City (practically a part of Pitts¬ 
burgh) have been already wrestling with the question of preventing the 
increase of the Smoke Nuisance, as evidenced by a letter to Mayor 
Noonan, asking several of the very questions which were placed before 
us for solution. The letter shows that they have no more knowledge 
of the problem than is usual among our citizens. 

Cincinnati with the same superior Pennsylvania coal brought to 
her doors by cheap river freights has long had a Smoke ordinance 
which as a solution of the problem is a complete failure. It provides 
(See Appendix IV) that anyone using a steam boiler without an effi¬ 
cient smoke preventing device shall be fined not less $50 nor more 
than $100 for each offence, and similar penalties are held over the 
men in charge of such boilers. 

The Supeivising Engineer who has charge of the enforcement of 
this ordinance wrote us that there was but one device in use which 
comes near being a smokeless furnace, and that “ must have perfect 
conditions .” Many steam jet devices are in use “but they soon burn out 
and are not economical in the use of fuel.” 

Devices with brick arches over the furnace have answered fairly 
well if the boiler is ample forthe work, u and they have a good draft” 
but expansion and contraction soon wrecks them and parties will not 
maintain them. 

When short of boiler capacity even the one device above men 
tioned as the best “will smoke like a tar kettle.” “A majority of 
boiler settings are too shallow between grates and boiler , so there is no 
room for the proper mixture of the gases, which together with a 
sluggish draft , due to low stacks in many cases, and the putting of two 
or three boilers into a chimney originally intended for one, makes a con¬ 
dition of thmgs hard to deal with, when the suppression of smoke 
is considered.” 


34 


Prevention of Smoke. 


“The intermittent work of a boiler adds to the difficulty, etc.” 
When it is remembered that Cincinnati need burn but 67 pounds of a 
much less smoke producing coal to our 100 pounds of a very smoky 
fuel, the failure of merely restrictive legislation is apparent. 

Chicago has long had a smoke ordinance and, if there were a 
sovereign virtue in such legislation, the Smoke problem should have 
been solved there long ago. 

For, while the common Illinois coals cost much more than in St. 
Louis such better and less smoky fuels as the Indiana block, 
Youghiogheny, and even Anthracite coals are biought to her at much 
lower figures than to us; in fact at prices which make them available 
as steam coals. 

Prices range about as follows: 


Illinois coal, 



Per Ton. 
$2.25. 

Kentucky lump coal, 


- 

3 - 35 - 

Indiana block coal, 


- 

2 75 - 

Indiana Hazel coal, - 


- 

2.25. 

Cumberland coal, 


- 

4.00. 

Youghiogheny coal, * 


- 

3 - 75 - 

Hard coal Screenings, 


- 

1.50. 

Hard coal (Anthracite), 


- 

5 - 75 - 


Mixtures, of much higher fuel value and much less smoky, have 
been, and are being tried to meet the stringent conditions of the smoke 
ordinance. F. I. mixtures of 15 to 33% hard coal screenings with 
Kentucky lump or Indiana block are being used with very fair success. 

In one plant a mixture of 

80% Indiana block at $2.75 per ton, - - $2 20 

with 20 % Anthracite screenings at $ 1.50 per ton, o 30 

gave a practically, smokeless mixture at - $2.50 

per ton, being only 25% per ton more than common Illinois coal, but 
possessing in practice a fuel value possibly 40% greater. 

With this mixture as high as 24^ lbs, of coal per square foot of 
grate have been burned per hour running the boilers 33% above 
rating, without coming under the censure of the Smoke Inspector, and 
that with a common furnace without any smoke preventing device. 

In spite of these facts, in spite of the simple and stringent Smoke 
ordinance (see Appendix V) which has been in force for some years, 




Prevention of Smoke. 


35 


stimulating the efforts of inventors and promoters of so-called Smoke 
Consumers, Chicago remains nearly as smoky as before. 

Finally, in the last week of 1891 a large meeting of prominent 
citizens, representing fifteen city clubs, and commercial bodies, was held 
and a Committee of Seven appointed to take the matter up in earnest. 
They have practically reached similar conclusions to those we have 
the honor to submit to you herewith, namely that an educational cam¬ 
paign must precede any restrictive legislation. 

A Society for the Prevention of Smoke has been formed, number¬ 
ing among its members some of the most prominent men in the 
business Community, and large sums of money subscribed to carry on 
the work. / 

Two experts have been appointed, at good salaries, who, with a 
corps of assistants, make tests of boilers and of smoke preventing de¬ 
vices, with a view to determining the exact conditions of each smoke 
problem and the limitations of devices offered. This follows out 
pretty closely the line of work your Committee had laid down as 
necessary, in their preliminary report of November last, which they 
now have the honor to give in full detail as their “Conclusions and 
Recommendations.” 

It is interesting to note that out of thirty-seven plants reported by 
the City Smoke Inspector for maintaining a Smoke Nuisance on Jan. 
1 st, 1892, six had in use well known and more or less meritorious 
“Smoke Consumers.” Nothing could better illustrate the necessity 
of careful tests to show promoter and purchaser alike the exact limi¬ 
tations of such devices, and their applicability to a given set of 
conditions. 


IX. Conclusions and Recommendations. 

While, as will have appeared from the foregoing, this Committee 
is unable to say that the practical problem of smoke prevention, under 
St. Louis conditions, is fully solved, we can say that substantial progress 
in that direction has been made. 

A number of meritorious devices are in the market. We can not 
recognize any of them as of unlimited or unconditioned effectiveness. 
What their practical limitations are, we are compelled to think that 
neither those who have invented, sold or used them, know. 

The smoke nuisance affects the whole community, and all are in¬ 
terested in getting rid of it. All will admit that there is a great but 


36 


Prevention of Smoke. 


uncalculated money loss, in destruction of goods and furnishings, in 
defacement of buildings, in labor and material expended in ihe vain 
effort to keep clean, and in increased necessity for artificial light; an 
a 3 sthetic loss through discouragement of the ornamentation of build¬ 
ings, homes and grounds; a sanitary loss in impaired health and prev¬ 
alence of lung and throat troubles; a population loss, in those who 
cannot or will not live in a begrimed city, and last, not least, a moral 
loss, in the effect on those who per force endure dirt and unwhole¬ 
someness. Great as the evil has been and is, its increase, if unchecked 
will be in a more rapid ratio than that of population. 

The time has come when a decided step should be taken. In that 
step, it is appropriate that the city through its government should take 
the lead, for the city authorities are themselves among the offenders. 
We would not advise any arbitrary action, but some pressure should 
be brought to bear upon those who produce the - great part of our 
smoke cloud; for, while some are alert and willing to spend money to 
abate their share of the evil, the majority may safely he supposed to 
be inert and as unready to make an effort to abate as they have 
proved unwilling or careless about responding to inquiries for facts. 
We do not think that the cloud can be entirely removed in the im¬ 
mediate future but we are sure that its density can be very materially 
reduced, not without cost, but without hardship to any. Yet all 
should be willing to exercise patience and even make some con¬ 
cessions. 

As an indispensable preliminary to repression, we think that 
authoritative and impartial determination should be made: 

ist. Of the practical bounds within which smoke emission may be 
confined now, taking emergencies and all valid excuses into account 
and defining them for the information of fuel consumers, and for the 
guidance of the authorities in dealing with them. 

2d. A determination of the quantitative and economical limita¬ 
tions of various devices and their adaptability to special requirements. 

To do this work a paid expert commission will be necessary; and 
the expense of such a commission should be borne by the public. 
That of preparing for test should be borne by the promoters of each 
device and the cost of testing, in part, by promoters and, in part, by the 
public. 

Finally, we call attention to a matter, seldom thought of in this 
connection, relating to the plan and construction of buildings. 

The modern business building nearly always contains a steam 


Prevention of Smoke. 


3 7 


plant for heating and other incidental uses. This plant is not regarded 
as revenue producing direct, and architects as well as owners are dis¬ 
posed to place it so as to occupy the least possible space. Hence it is 
in most cases inconveniently located, cramped for room and but little 
regard paid to ventilating. Flues and chimneys are often unskillfully 
proportioned, and the comfort of attendants so little considered that 
they can do no better than stuff the furnace and go out to breathe. 

Recommendations. 

In view of the facts and considerations, presented above, your 
Committee would respectfully make the following recommendations 
and urge immediate action upon them:— 

I. The introduction in the Municipal Assembly of two ordinances, 
(drafts of which are herewith presented).' 

A. An Ordinance Declaring the Emission of Dense Visible 
Smoke to be a Nuisance ’and Providing for the Suppression thereof 
within one hundred and eighty days after the enactment of this ordi¬ 
nance. 

B. An Ordinance Authorizing and Providing for the Making 
of Regulations Limiting and Defining Permissible Smoke Emission; 
for the Testing of Smoke Preventing Devices, and for the Making of 
such Tests and Experiments as may be Deemed Advisable with a view 
to the Abatement or Suppression of the Smoke Nuisance. 

II. The introduction in the Municipal Assembly of an amend¬ 
ment to the present Boiler Inspection Ordinance with a view to reg¬ 
ulating the size, proportions and fittings of boilers to be erected here¬ 
after and the accommodations to be provided for such boilers. 

III. That steps be taken at once to diffuse as thoroughly as possi¬ 
ble among the public especially housekeepers, manufacturers and rail¬ 
road officials such facts and figures and right information concerning 
these as may aid them in the early general adoption of smokeless fuels 
so far as they may be applicable, as: 

A. In domestic establishments, anthracite, coke or fuel gas. 

B. In industrial furnaces, other than boiler plants, coke, fuel 
gas or oil. 

C. For all switch engines and such as operate within the City 
limits, coke. 

The following are drafts of the ordinances suggested:— 


Prevention of Smoke. 


38 

An Ordinance, Declaring the Emission of Dense Visible Smoke to be 

a Nuisance, and to Provide for the Suppression Thereof. 

Be it ordained by the Municipal Assembly of the City of St. Louis 
as follows: 

Section i. —The emission into the open air of dense visible smoke 
within the corporate limits of the City of St. Louis is hereby declared to 
be a nuisance. The owners, occupants, managers or agents of any 
establishment, locomotives or premises from which dense visible smoke 
is- habitually emitted or discharged shall be deemed guilty of a mis¬ 
demeanor, and, upon conviction thereof shall pay a fine of not less than 
ten nor more than one hundred dollars. And each and every day 
wherein such smoke shall be emitted shall constitute a separate 
offense. 

Section 2.—The President of the Board of Public Improvements 
is hereby authorized and directed to appoint with the approval of 
the Mayor, such inspectors, not exceeding five in number, as may be 
necessary to carry out the provisions of this ordinance. Said inspec¬ 
tors shall receive a salary of one hundred dollars a month each, pay¬ 
able monthly. 

Section 3.—The inspectors shall have a right to enter, in the per¬ 
formance of their duties, at reasonable hours upon all premises other 
than dwelling houses occupied Dy less than four families or tenants. 
They shall collect evidence of the facts in cases of the violation of this 
ordinance, and, with the approval of the President of the Board of 
Public Improvements in each case shall report the same to the City 
Attorney for prosecution. The inspectors shall be guided in the per¬ 
formance of their duties, by instructions given by the Board of Public 
Improvements, and approved by the Mayor, from time to time. 

Section 4.—This ordinance shall take effect at the expiration of 
six months after its approval by the Mayor. 


An Ordinance, Authorizing and Providing for the Making of Reg¬ 
ulations Limiting and Defining Permissible Smoke Emissions, and 
for the Testing of Smoke Prevention Devices, and for the making 
of Such Tests and Experiments as may b*e Deemed Advisable 
With a View to the Abatement or Suppression of the Smoke 
Nuisance. 

Be it ordained by the Municipal Assembjy of the city of St. Louis 
as follows: 


Prevention of Smoke. 


39 


Section i. —The President of the Board of Public Improvements 
is hereby authorized and directed to appoint with the approval of the 
Mayor, a commission composed of three competent persons, who shall 
not be directly or indirectly interested in the manufacture, sale or con¬ 
struction of any furnace or other article having practical relation to the 
production or prevention <ff smoke. 

Said commission shall ascertain, and report to the Board of Pub¬ 
lic Improvements, the conditions and liabilities under which manufac¬ 
turing and other parties cannot wholly or reasonably prevent the oc 
casional production and emission of dense visible smoke. Such ascer¬ 
tained conditions and liabilities, when approved by the Board of Public 
Improvements and Mayor shall be published and thereafter shall con 
stitute instructions to guide and limit the officials charged with the en¬ 
forcement of smoke suppression ordinances. And it shall be a valid 
and sufficient defence against any complaint, that the offence charged 
comes within such recognized condititions and liabilities 

Said commission shall conduct and make practical tests of all de¬ 
vices for the prevention or suppression of smoke which shall be sub¬ 
mitted to them, in accordance with the conditions hereinafter set forth, 
and shall prepare detailed reports, stating the facts and conclusions 
based thereon, as to f hc efficiency of each such device, the conditions 
of its successful operation and the limitations to its efficiency. Said re¬ 
port shall be made promptly when any test is completed, to the Board 
of Public Improvements, which report may be rejected by said Board 
if found to be unfair or untrue. If accepted by said Board the report 
shall be published for the information of the Public. Provided how¬ 
ever, that such acceptance and publication shall not be constructed as 
an endorsement of ihe report by the City of St. Louis or as a recom¬ 
mendation for or against the device passed upon. 

Sa : d Commissioners shall also be called upon, by the Piesident of 
the Board of Public Improvements, to make such tests and experiments 
as may in his judgement be needed to determine the applicability of 
special or smokless fuels to domestic, locomotive or other uses, with a, 
view to the abatement or suppression of smoke, and shall prepare 
detailed reports of the results together with such conclusions and 
recommendations as in their judgment may be warranted by the facts: 
said reports to be made promptly and printed for the information of 
the public. 

Section 2.—The Commissioners authorized by the preceding 
section shall receive in compensation for their services in ascertaining 


40 


Prevention of Smoke. 


and reporting the conditions and liabilities of Smoke Suppression the 
sum of one thousand dollars each, payable upon the certificate of the 
President of the Board of Public Improvements that such report has 
been made to, and accepted, by the Board of Public Improvements. 
For their services in conducting tests of devices and making report 
thereon they shall each receive the sum of Seventy-five Dollars for 
each device tested and reported, and for conducting the special tests 
and experiments, as provided in the preceeding section, one hundred 
dollars for each series of tests or experiments together with a full report 
of the same. Said respective sums to be paid on the certificate of 
the President of the Board of Public Improvements that the report of 
such test h is been received and accepted by said Board. 

Incidental and necessary expenses, for the above described in¬ 
vestigations and tests, shall be allowed and paid for as other expenses 
of the office of the President of the Board of Public Improvements. 

Section 3.— Any party having or claiming to have a plan or 
device whereby smoke can be prevented or suppressed, and desiring to 
have the same subjected to a practical test and determination, may do 
so on the following conditions: 

First— He or they shall notify in writing the President of the 
Board of Public Improvements that such a test is desired, and with 
such notice shall file a full and complete discription of the device with 
all necessary drawings to show its character, construction and mode of 
operation. Accompanying such notice shall be a certificate of the 
City Treasurer that there has been deposited with him to the account 
of contract and other deposits the sum of one hundred dollars. 

Second. — If the President shall judge that the public interest and 
the probable merits of the device justify a test, at the City’s expense, 
he shall instruct the Commission to make it whereupon the sum 
deposited shall become the property of the City of St. Louis and shall 
be credited to the fund for testing smoke prevention devices If the 
said President shall judge that the public interests or the probable 
merits of the divice do not justify a test, at the City’s expense, he may 
refuse it, whereupon the sum deposited shall be returned to the depos¬ 
itor. But the party interested may pay into the City treasury the sum 
of four hundred dollars to the credit of the fund for testing smoke 
prevention devices, and, upon the presentation of the Treasurer’s certifi 
cate to that effect, the President of the Board of Public Improvements 
shall order the Commission to make the test. 

Third .—The party or parties submitting a device shall erect the 


Prevention of Smoke. 


same at the place designated by the Commission, or at such other 
place as the Commission may approve of, at their own cost and ex¬ 
pense under their own supervision, with such provisions' for the at¬ 
tachment of instruments as the Commission may require, and, when 
fully ready, shall deliver the premises and equipment to the Commis¬ 
sion. 

If the place is furnished by the Commission such erection and 
delivery shall be made within thirty days after the place is put at the 
disposal of such persons, and after the test is closed said device and 
all its belongings shall be removed within 15 days after notice to that 
effect. 

Fourth.-— If after test is begun, alterations or improvements are 
desired to be made the party interested must proceed as if submitting 
a new plan or device. Unless the several Commissioners shall each 
consent to such alterations and waive all claim for compensation for 
a partial test. 

Section 4.—Whenever the Mayor shall be of the opinion that 
the public interest does not warrant the further testing and reporting 
on devices, under the authority of the City of St. Louis, he shall notify 
the President of the Board of Public Improvements to that effect, in 
which event the existence of the Commission, hereby authorized, shall 
terminate when tests already in hand shall have been completed and 
reported as herein provided. 

Your Committee believes that these two proposed ordinances 
embody the best form of municipal action in the premises. While, 
possibly, further discussion on the part of all interested in the subject 
may suggest certain modifications, the main point must be kept in 
view. It is, that the City government owes it to the manufacturing 
interests to present—first the ways and means in which smoke may be 
prevented under existing economic conditions, before it has the right 
to pass or enforce smoke ordinances similar to those of Cincinnati and 
Chicago. 

We sincerely believe that when the means are once shown clearly, 
the public spirit of the large majority of our manufacturers will induce 
them to adopt such means without waiting for any mandatory law, 
Very respectfully submitted, 

E. D. Meier, Chairman. 
William B. Potter, 

Robert E. McMath, 

C. E. Jones, Committee. 


42 


Prevention of Smoke. 


APPENDIX I. 

To Steam Users of S. Louis: 

Gentlemen .—The undersigned Committee, appointed by the 
Mayor of the city, at a recent meeting of manufacturers and others, 
called to consider the smoke nuisance, request your co operation by 
answering the following questions, or as many of them as you can 
answer correctly with reference to your own boiler plant and daily ex¬ 
perience. The Committee will consider your communication confiden¬ 
tial, if you so desire it, using the facts and quantities only, without re¬ 
ferring to the plant to which they refer, in making up a tabular state¬ 
ment, showing the exact extent of the difficulties wnich the solution of 
this problem presents. 

1. Please state the number and size of your boilers, i. e. diameter 
and length, and the number, diameter and length of flues or tubes in 
each; please give also the clear length .and clear width of grate under 
each boiler or battery, as well as the clear height from top of grate to 
bottom of boiler. 

2. Please state diameter or square, and height of your chimney, 
counting the height from the level of the grade. 

3. What kind of coal (name mine if possible), do you use. and is 
it “ Run of the Mine,” “ Slack,” “ Nut ” or “ Lump?” and how many 
pounds or bushels do you burn per hour? 

4. Is your boiler plant taxed to its full capacity, or have you any 
margin over your actual necessities, and if so, how much? 

5. Does the work required of your boilers vary during the day, 
and within what limits, and what is the nature of the variation, i. e. fre¬ 
quent and sudden, or regular and at long intervals? 

6. How many pounds of water do you evaporate per pound of 
such coal as you use, taking actual weights and measurments? State 
also in this connection the temperature of your feed water as it enters 
the boiler, and the steam pressure you generally carry as shown by 
guage. In answering this question it is not necessary to make an ex¬ 
pert test, but you can no doubt give the amount of coal for a number 
of months back, from your coal bills, and your meter readings for 


Prevention of Smoke. 


43 


the same time, and enable the Committee to make this computation. 
If you have ever used any smoke consumer, or smoke preventing 
furnaces or devices, or are now using same, please state the results as 
compared with those obtained with plain furnaces and plain grates. 

7. How many pounds of coal per square foot of grate do you burn 
per hour without making smoke? 

8 . How many pounds of coal per square foot of grate do you burn 
per hour with no smoke except for one or two minutes after each firing, 
or how long after each firing does smoke continue? 

Please send replies to this Circular to the 4 Smoke Prevention 
Committee,” care Commissioner of Buildings, City Hall. 

APPENDIX II. 

The loss or consumption of Steam by steam jet blowers is found 
to be very large. Experiments made at the New York Navy Yard with 
five different types of nozzles are reported in Engineering News of 
September 19th, 1891. 

The nozzle consuming the largest amount of steam was an annular 
slot. As its exact dimensions are not given we cannot well compare 
it with the o hers. 

The other four compared as follows: 

Single Round Hole of 

l /l 6 DIAM. Vs DIAM. ®/ 6 4 DIAM 
Per cent of total steam, 8.3% 12% 14% 

Pounds steam per hour, 7.5 15.8 19.06 

Loss in H. P., 0.25 0.53 0.653 

As the supply pipe to the nozzles was very small it is highly prob¬ 
able that the loss by the larger nozzles would have been proportionately 
greater had the supply been ample. 

APPENDIX III. 

As further illustrating the losses due 10 smokeless combustion we 
append the average results of some interesting practical tests made in 
Chicago, bv Mr. Wm. C. D. Gillespie, M. E., Chief Engineer of. the 
Rookery Building. The aim was to produce smokeless combustion at 
any cost. The coal used was much less smoky than our St. Louis 
fuels viz. Indiana Block coal whose price precludes its use under 
boilers in this city. 


33 Holes, Each of 

V32 DIAM. 

20.7 % 

30 

1.0 


44 


Prevention of Smoke. 


The tests were divided into three series, each recording the aver¬ 
age results reached by improvements in the furnace. They show both 
a decrease in power and a loss in economy the more they approach 
perfectly smokeless combustion. 

The boiler was of the horizontal tubular type 60" diameter by 14 ft. 
long, with 46 tubes 4"xi4 ft. It had 620 sq. ft. of Heating Surface and 
16 ft. of grate area, a very favorable proportion for economy The 
furnace was of the fire brich arch type, the arch being very long, 9 ft. 
in all, of which all but i-J- ft. were in front of the boiler. There is pro¬ 
vision for air admission over the fire The grate as well as the arch 
incline downwards from the fire front to the boiler. 

The record, condensed to its essentials is as follows: 


Tests. 

First Series. 

Second Series. 

Third Series 

Time. 

4 days of 9 

5 days of 9 

5 days of 9 

Pounds Coal burned per sq. ft. 

hrs. each. 

hrs. each. 

hrs. each. 

grate per hour. . . . 

24-34 

24-59 

23.82 

Horse power developed. . . 

102 

93 

89 

Boiler ran above rating. . . 

25 % 

13 % 

10% 

Conditions as to smoke. . . 

Moderate 

Smoke Much 

Practically 

Loss in power by reducing 

Smoke 

Reduced 

Smokeless 

smoke.. 

Loss in economy by reducing 

0 

12% 

15 % 

smoke. 

0 

772 % 

I37s% 


Mr. Gillespie writes us later (March 9th, ’92) that he has made 
further improvements by which he gains considerably in economy. 

APPENDIX IV. 


Cincinnati Smoke Ordidance. 

An Act to Provide for the Better Production of Human Life Against 
Fire, and Regulate the Construction and Management of Steam- 
Boiler Furnaces in Cities of the First and Second Grades of the 
First Class. 

Section 4^— Every steam-boiler furnace used within the corporate 
limits of any city of the first grade of the first class shall be so con¬ 
structed or altered, or have attached thereto such sufficient smoke pre- 






Prevention of Smoke. 


45 


ventives as to produce the most perfect combustion of fuel or other 
material from which smoke results, and so as to prevent the produc¬ 
tion and emission of smoke therefrom so far as the same is possible. 
And any person or persons, association or corporation, being the 
owner or lessee, or having control of any such steam boiler furnace 
(who) shall use or allow the use of any such steam-boiler furnace 
which shall not be so.constructed, or if already constructed at the time 
of the passage of this act shall not be so altered, or shall not have 
attached thereto such efficient smoke preventives as to produce the 
most perfect combustion of fuel or other material from which smoke 
results, and so as to prevent the production and emission of 
all smoke therefrom so far as the same is possible, or shall 
fail to keep such steam-boiler furnace for the prevention of 
smoke, and such smoke preventives in good and efficient order 
and operation, shall be subject to a fine of not less than twenty 
dollars nor more than fifty dollars for the first offense, and for each 
subsequent offense shall be fined not less than fifty nor more than one 
hundred dollars. And no steam-boiler furnace shall hereafter be con¬ 
structed in any city of the first grade of the first class, except in ac¬ 
cordance with the requirements of this section, under the penalty of 
fifty dollars for each offense. 

Section 5.—Every person having charge of the igniting, making, 
stoking, feeding, or attending any such furnace and any smoke pre¬ 
ventives attached thereto in good and efficient order and use, that the 
least possible smoke shall be produced and emitted therefrom, and 
any such person who shall fail or neglect to so ignite, make, stoke, 
feed, or attend such furnace fire that the least possible smoke shall be 
produced or emitted therefrom, or shall fail or neglect to keep such 
such furnace or smoke preventives attached thereto in good and 
efficient order and use, or shall hinder or disarrange any such furnace 
or smoke preventives attached thereto, shall be subject to the payment 
of a penalty of not less than twenty dollars nor more than fifty dollars 
for the first offense, and not less than fifty dollars nor more than one 
hundred dollars for each subsequent offense. 

Section 6.— The mayor of the city in every city of the fir&t grade 
of the first class shall appoint a person of suitable qualifications as 
supervising engineer, who shall hold his office for the term of two 
years, from and after the date of his appointment, and until his suc¬ 
cessor is appointed and qualified; and he shall have authority to sup¬ 
ervise and require all steam-boiler furnaces in such city of the first 


46 


Prevention of Smoke. 


grade, of the first class to be constructed, or if already constructed to- 
be so altered or have attacked thereto such efficient smoke preventives, 
so as to produce the most perfect combustion of the fuel or other 
material from which smoke results, and so as to prevent the production 
and emission of all smoke therefrom so far as the same is possible, and 
he shall further have authority to supervise the igniting, making, stok¬ 
ing, feeding, and attending such steam boiler fyrnace fires; and die 
shall have further authority, in the performance of the duties of his 
office, to enter any steam-boiler or engine-room, or any building not 
occupied exclusively as a private residence, and any person or persons 
hindering or obstructing him in the performance of such duties shall 
be subject to a fine of not less than twenty dollars nor more than fifty 
dollars, or imprisoned in the workhouse for a period not exceeding 
thirty days. 

Section 9.—The penalty for any violation of the provisions of 
this act, not otherwise especially provided for, shall be not less than 
twenty dollars, nor more than fifty dollars, for the first offense, and not 
less than fifty, nor more than one hundred dollars, for each subsequent 
offense. 

Sectton 10.—All acts or parts of acts inconsistent or in conflict 
with this act, be and the same are hereby repealed. 

Section ii.— This act shall go into effect and be in force from 
and after its passage. 


APPENDIX V. 

Chicago Smoke Ordinance. 

Section 1650.—The emission of dense smoke from the smoke¬ 
stack of any boat or locomotive, or from any chimney anywhere within 
the City, shall be deemed, and is hereby declared to be a public 
nuisance; provided , that chimneys of buildings used exclusively for 
residences shall not be deemed within the provision of this ordinance. 

Section 1651.—The owner or owners of any boat, or locomotive 
engine, and the person or persons employed as engineer or otherwise, 
in the working of the engine or engines in said boat or in operating 
such locomotive, and the proprietor, lessee, or occupant of any build¬ 
ing, who shall permit or allow dense smoke to issue or be emitted 
from the smokestack of any such boat or locomotive, or the chimney 


Peevention of Smoke. 


47 


of any building within the corporate limits, shall be deemed and held 
guilty of creating a nuisance, and shall for every such offense be fined 
in a sum not less than five dollars, nor more than fifty dollars. 

Section 1652.—It shall be the duty of the Commissioner of 
Health and the Superintendent of Police, to cause Sections 1650 and 
1651 of this article to be enforced, and to make complaint against and 
cause to be prosecuted all persons violating the same. 





0 021 993 


i 


St. Louis, Mo.: 

W. H. O’Brien & Co., Printers, 914 Locust St., 
1892. 


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